The spondylodesis implant of this kind known from DE 31 32 520 A1 serves for the adjustable fixation of two immediately adjacent vertebrae. The threaded spindles assigned to the two connection pieces are made in one piece in a coaxial arrangement, whereby between the two threaded spindles a connecting outer hexagonal piece is provided, which serves for the application of a turning tool for the common rotation of the threaded spindles. The threaded spindles as well as the corresponding threaded nuts by means of which the connection pieces are guided on their respective threaded spindles rotate in opposite senses, so that during the concurrent rotation of the threaded spindles the two connection pieces are either moved towards each other or away from each other according to the direction of rotation.